Gullimair travels east: drivers of party system institutionalization in Asia in comparative perspective

In this article, we apply Mair's concept of 'party system closure' to Asian party systems, with particular comparison with his native continent, Europe. Building on Mair's (2001) conceptualization and Casal B & eacute;rtoa and Enyedi's (2021) operationalization of party system institutionalization (PSI), which demonstrates the importance of looking at the supply-side of PSI and the superiority of closure over electoral volatility as a measure of PSI, this article is the first to examine the determinants of party system closure in Asia. Introducing and analyzing a new dataset covering 136 elections and 235 cases of government formation in 23 Asian democratic party systems, and using Casal B & eacute;rtoa and Enyedi's (2022) original dataset for Europe, we find that (1) the negative effect of direct presidential elections is significantly higher in Asia than in Europe, (2) in contrast to Asia, where historical legacies have a detrimental impact, they are not statistically significant in Europe, and (3) parliamentary fragmentation hinders systemic closure to a similar extent in both continents. Our analysis has important implications for the future stability of party systems in both Asia and Europe where the number of (new) parties has exponentially increased in recent years.